This document provides grammar rules for countable and uncountable nouns in English. It discusses how countable nouns can be singular or plural, and how we use words like "a/an" with singular nouns and pluralize nouns by adding "s" or changing the word. It also explains that uncountable nouns are usually materials, foods or ideas that cannot be counted directly, but can be made countable by referring to them in containers. The document provides examples like cups of coffee to illustrate countable vs. uncountable nouns and quizzes the reader to test their understanding.